Let you know brucite in a minute

1 brucite name brucite


2 composition of brucite. Brucite has a simple chemical composition and the molecular formula is Mg (OH) 2. Brucite is a rare high magnesium mineral in nature. Its theoretical chemical composition is 69.12% MgO and 30.55% H2O. Brucite produced in nature often contains impurities such as Fe, Mn, Zn and Ni. These impurities exist in isomorphism and form a continuous or discontinuous solid solution series, Constituent end member subspecies: ferrihydrite (containing FeO 10%), manganese Hydrite (containing MnO 18%), zinc Hydrite (containing ZnO 4%), nickel Hydrite (containing NiO 2.5%). The associated minerals of brucite include serpentine, calcite, dolomite, magnesite, magnesium silicate minerals, periclase, diopside and talc.


3 brucite property brucite single crystal is in thick plate shape, common flake aggregate, sometimes fibrous aggregate, which is called brucite; White to light green, reddish brown if containing manganese or iron. The color change of brucite depends on the content of the mixture. For example, the variants containing iron and manganese impurities show yellow or maroon; Transparency; The cleavage surface is pearl luster, the fresh crystal surface and fracture surface are glass luster, and the fibrous brucite is silk luster; Hardness 2.5; Specific gravity 2.3 ~ 2.6g/cm3.


4 use of brucite brucite is an industrial mineral with special value because of its high content of useful components and less harmful impurities. In addition, its unique physical and chemical properties are different from other types of magnesium containing mineral raw materials.


4.1 flame retardant


The water content of brucite is particularly high, about 31%; The differential thermal analysis of brucite shows that its thermal decomposition and dehydration temperature is between 420 ~ 520 ℃, which is close to the combustion temperature of general articles, so it can be used as fire retardant coating and flame retardant. Brucite fire retardant coating has the characteristics of light bulk weight, good decoration, strong weathering resistance, good fire resistance and no peeling after fire. It can be used for surface coating of ships, high-grade houses, etc. The flame retardant based on brucite has good flame retardancy and reinforcement, non-toxic, pollution-free and weathering resistance. It is also suitable for high temperature molding process.


4.2 fibrous brucite as reinforcing and reinforcing fiber


Because fibrous brucite is similar to chrysotile asbestos in heat resistance, insulation, alkali resistance and tensile strength, and the dissolution of fibrous brucite in acid is much greater than that of asbestos, and fine dust is easy to be dissolved in weak acid, it is difficult to stay in human body and has no possibility of carcinogenesis. Therefore, fibrous brucite has no pollution to the environment and no risk of carcinogenesis to human body, It can completely replace chrysotile asbestos in many fields.


4.3 paper industry


Brucite can be used as papermaking filler together with calcite because of its high whiteness, good peeling property, strong adhesion and basically no water absorption, so as to change papermaking from acid method to alkali method and reduce pulp water pollution. In the paper industry, brucite replaces lime in the production of magnesium sulfite pulp, which can absorb SO2, make the waste pulp water recyclable, and greatly reduce the pollution of the waste pulp water to the environment. Because brucite does not absorb water in the air, it can also be used as the filler of moisture-proof packaging paper.


4.4 environmental protection


Due to the composition characteristics of brucite, it can be used for neutralization treatment of acid wastewater. It not only has process advantages over traditional alkali substances (such as sodium hydroxide, calcium hydroxide, etc.) in many aspects, but also can greatly reduce the cost in product treatment and emission. Brucite can also be used as flue gas desulfurizer. Adding brucite to boiler dyes can reduce the harm of high mercury and high sulfur dyes to boilers and reduce the emission of sulfur dioxide and other harmful substances.


4.5 magnesia high temperature refractory


Magnesite and dolomite are burned into magnesium and calcium oxides at high temperature, then ground, mixed with organic binder, pressed into mold, and then calcined twice to produce refractory brick products. This kind of refractory brick can replace the expensive MgO high temperature refractory brick in the metallurgical industry. The advantage of this method is that there is no separation of brucite and dolomite, and the cost and technical conditions are greatly reduced.


4.6 other applications


(1) Brucite mineral fiber rubber plate can be made of fibrous brucite and rubber to replace the traditional asbestos rubber plate;


(2) The very dense periclase aggregate with high thermal conductivity and electrical insulation can be prepared from brucite by electric melting, and its service life is 2 ~ 3 times longer than that of fused magnesite;


(3) When brucite and dolomite are calcined, the products can be used in iron and steel manufacturing industry to remove impurities such as P and s and treat slag;


(4) The product of brucite and calcium carbonate calcined at 800 ~ 1150 ℃ can be used as decolorizer to treat sugar beet juice in sugar industry.


5 reserves and distribution of brucite up to now, the total proved reserves of brucite resources in China have exceeded 25 million tons. Fengcheng, Liaoning Province has the richest brucite resources in China, with a reserve of 10 million tons; The proved brucite reserves in Ningqiang area of Shaanxi Province are 7.8 million tons; Jilin Ji'an has proven brucite reserves of 2 million tons.